Packing containers

ABSTRACT

A cardboard container comprising a first tube lined internally and externally with hot-sealed aluminum-polyethylene, polyethlene-paper or the like, and a second tube inside the lined tube, the first tube being closed by crimped end caps and externally circumferentially partially incised, the incision being closed off by an adhesive tape.

United States Patent (72] Inventor Pierre Jean Riboud [50] Field of Search 229/5 1, 311 Levallois-Perret. France 4.5 5.6, 93; 206/3 21 Appl. No. 806,877 [22] Filed Mar. 13, 1969 [56] References Cited 1 1 Patented F 2, 1971 UNITED STATES PATENTS I 1 Assignee Ammyme Lincmsm 53,765 4/1866 Ackley etal 229/31 Pans, France 1,939,339 12/1933 Dolan 206/3 [32] Priority Aug. 14, 1968 [3 3 France [3 l 1 3547 [54] PACKING CONTAINERS 10 Claims, 1 Drawing Fig.

[52] U.S. Cl 229/51, 229/3.l 206/3 [51] Int. Cl B65d 3/22 Primary Examiner-David M. Bockenek Attorney-Amold Robinson ABSTRACT: A cardboard container comprising a first tube lined internally and externally with hot-sealed aluminumpolyethylene, polyethlene-paper or the like, and a second tube inside the lined tube, the first tube being closed by crimped end caps and externally circumferentially partially incised, the incision being closed off by an adhesive tape.

ln an unpressurized aircraft flying at high altitude, the low external air pressure and temperature are liable to cause sealed cardboard packings to fail as a consequence of the breaking of the seal by the high pressure inside the packing. This phenomenon is encountered especially where the packing is in the form of a box with a flush lid, and where the seal is obtained by applying a strip of adhesive tape around the joint between the lid and the box.

in this type of packing which is particularly suitable as a container for munitions, the adhesive tape, under the effect of the internal pressure, stretches by some few microns or hundredths of a millimetre. This stretching allows the high pressure inside the box to collapse.

During descent of the aircraft, the pressure imbalance between the interior of the package and the exterior, changes in direction so that then a suitable adhesive tape can operate as a valve which closes to prevent any penetration of humid air to the interior of the enclosure, which latter is then under slight vacuum, but as a result of the reduction in temperature at high altitude when the stretching of the tape occurs there may be a deterioration of a permanent kink which may be such as to cause the tape to crack and so prevent it from acting as a valve.

An object of the present invention is to provide a packing container of cardboard or similar material, which constitutes a sealed enclosure which is insensitive either to pressure gradients or to substantial reductions in temperature during pressure gradients.

The invention therefore consists in a packing container of cardboard or the like comprising a tube lined with a sealing internal barrier layer, which tube is partially nicked or incised to a sufiiciently shallow depth to ensure that the sealing barrier is not affected, and which is closed by crimped end caps which ensure continuity of the seal.

The pressure-tight barrier can be constituted, for example, by arrangements of hot-sealed aluminium-polyethylene, hotsealed polyethylene-paper, hot-sealed polypropylene-paper, or hot-sealed polyvinylchloride-paper, or by using compounds of this kind on resin-bonded paper substrates. In the latter case the substrates must be treated to ensure that they do not absorb water when cut by heavy calandering for example or the introduction into the body of the paper of products which prevent water being absorbed through the nick.

The partial nicking or incision of the tube makes it possible to open the package simply by twisting the two sections of the tube between the hands, this rupturing the pressure-tight internal layer.

The nicks can be closed off externally using a very thin adhesive tape for example having a thickness of five to six-hundredths of a millimetre, so that continuity and sealing of the exterior is reestablished. The tape substrate can be constituted for example by nonplasticized vinylchloride.

An exemplary embodiment of the invention will now be described with reference to the drawing forming part of this specification, the single FIG. of which is an axial section through the packing container.

The packing container in this FlG. comprises a tube 1, inside which there is arranged an inner tube 7 whose length is slightly shorter. The tubes 1 and 7 are produced in the conventional way be straight or spiral windings of sheets or strips of cardboard or similar semirigid material.

The tube 1 is lined internally with a sealing layer 2 and externally with a sealing layer 3 and is closed off by crimped end caps 4 which are of metal or some other impervious material. Each of these caps has a deep cut 40 the depth being for example of the order of mm. and the cup portion is fitted in the tube 1. Preferably, prior to the crimping of the end caps 4, the ends of the tubel are dipped in a flexible varnish.

The tube 1 is partially incised or nicked around the whole of its periphery, as indicated at 5, although the incision should not be deep enough to reach the layer 2, and this incision is closed off by a very thin adhesive tapre 6 which ensures continuity and sealing of the exterior. he packing retains its rigidity thanks to the inner tube 7.

The product being packed is introduced prior to the crimping in position of the second end cap 4. To open the package, it is merely necessary to twist the package in the hands, the two sections of the tube 1 separating along the line of the nick 5. The shorter section of the tube 1 then acts as a cover which can be replaced by sliding it over the inner tube 7.

The packing which has just been described, has an extraordinarily high degree of pressure tightness, something which has been confirmed by using a vacuum tank filled with water.

During testing, the external adhesive tape 6 is found to extend under the effect of the vacuum by reason of the higher pressure inside the packing, and allows part of the air contained in a space situated between the sealing internal layer 2 and the sealing external layer 3, to escape. On the other hand, none of the higher pressure air contained inside the continuous sealing internal layer 2, can escape.

When the pressure in the vessel is returned to atmospheric pressure, a small quantity of water may be found to have penetrated between the two sealing layers 2 and 3 by reason of the discontinuity created by the slight stretching of the external adhesive tape 6, and in spite of the valve effect. However, no trace of moisture, water or water vapor is found to penetrate the continuous enclosure defined by the sealing internal layer and the metal end caps.

I claim:

1. A container comprising a first tube of cardboard or the like, said tube being lined internally and externally with a sealing material which comprises a layer of plastic, and a second tube disposed in said first tube such that the outer surface of said second tube is in contact with the internal sealing material on said first tube, said first tube having one or more perforations passing through said external lining material and into said first tube but terminating short of said internal lining material on said first tube as to not impair the continuity of said internal lining material, said perforations being disposed to facilitate opening the package by twisting said second tube to separate it into two sections.

2. A container according to claim 1 wherein said first tube is longer than said second tube, and an end cap within the end portion of said first tube, said end cap having a sidewall portion bearing against said internal sealing material of said first tube and having another portion extending over the longitudinal end of said first tube and bearing against the external sealing material of said first tube.

3. A container according to claim 2 wherein the end of said first tube is impregnated with a flexible varnish before said end cap is attached.

4. A container according to claim 1 further comprising a band of adhesive material on said external sealing material and disposing over said perforations to provide continuity of said external sealing material.

5. A container according to claim 1 wherein said sealing material further comprises a substrate to which said plastic is bonded.

6. A container according to claim 5 wherein said plastic is polyethylene.

7. a container according to claim 5 wherein said plastic is polypropylene.

8. A container according to claim 5 wherein said plastic is polyvinylchlori de.

9. A container according to claim 5 wherein said substrate is aluminum.

10. A container according to claim 5 wherein said substrate is paper. 

1. A container comprising a first tube of cardboard or the like, said tube being lined internally and externally with a sealing material which comprises a layer of plastic, and a second tube disposed in said first tube such that the outer surface of said second tube is in contact with the internal sealing material on said first tube, said first tube having one or more perforations passing through said external lining material and into said first tube but terminating short of said internal lining material on said first tube as to not impair the continuity of said internal lining material, said perforations being disposed to facilitate opening the package by twisting said second tube to separate it into two sections.
 2. A container according to claim 1 wherein said first tube is longer than said second tube, and an end cap within the end portion of said first tube, said end cap having a sidewall portion bearing against said internal sealing material of said first tube and having another portion extending over the longitudinal end of said first tube and bearing against the external sealing material of said first tube.
 3. A container according to claim 2 wherein the end of said first tube is impregnated with a flexible varnish before said end cap is attached.
 4. A container according to claim 1 further comprising a band of adhesive material on said external sealing material and disposing over said perforations to provide continuity of said external sealing material.
 5. A container according to claim 1 wherein said sealing mAterial further comprises a substrate to which said plastic is bonded.
 6. A container according to claim 5 wherein said plastic is polyethylene.
 7. a container according to claim 5 wherein said plastic is polypropylene.
 8. A container according to claim 5 wherein said plastic is polyvinylchloride.
 9. A container according to claim 5 wherein said substrate is aluminum.
 10. A container according to claim 5 wherein said substrate is paper. 